130 likes | 316 Views
Calculus I (MAT 145) Dr. Day Fri day March 1, 2013. Return Gateway Derivatives Quiz # 2 (#3 Next Week!) Derivatives of Composite Functions: The Chain Rule (3.4) Implicit Differentiation (3.5 ) Derivatives Involving Logarithms (3.6) Logarithmic Differentiation (3.6) Assignments.
E N D
Calculus I (MAT 145)Dr. Day Friday March 1, 2013 • Return Gateway Derivatives Quiz #2 (#3 Next Week!) • Derivatives of Composite Functions: The Chain Rule (3.4) • Implicit Differentiation (3.5) • Derivatives Involving Logarithms (3.6) • Logarithmic Differentiation (3.6) • Assignments MAT 145
Using Derivative Patterns For s(t) = cos(2t): • Calculate s’(t)and s’’(t). • Determine an equation for the line tangent to the graph of s when t = π/8. • Determine the two values of t closest to t = 0 that lead to horizontal tangent lines. • Determine the smallest positive value of t for which s’(t) = 1. • If s(t) represents an object’s position on the number line at time t (s in feet, t in minutes), calculate the object’s velocity and acceleration at time t = π/12. Based on those results, describe everything you can about the object’s movement at that instant. MAT 145
THE CHAIN RULE WORDS BY: JOHN A. CARTER TUNE: "CLEMENTINE" Here's a function in a function And your job here is to find The derivative of the whole thing With respect to x inside. Call the outside f of u And call the inside u of x. Differentiate to find df/du And multiply by du/dx. Use the chain rule. Use the chain rule. Use the chain rule whene'er you find The derivative of a function compositionally defined. MAT 145
Derivatives of Implicitly Defined Functions (3.5) An implicitly defined function is: A function whose relation among the variable is given by an equation for which the function has not been explicitly stated. In the equation x2 + y2 = 25, y is an implicit function of x because the equation doesn’t explicitly express y in terms of x. MAT 145
Derivatives of Implicitly Defined Functions (3.5) • To calculate the derivative of an implicitly defined function: • Assume a functional connection among the variables. If x and y are present, assume y is a function of x. • Calculate the derivative of each term in the equation. Because we don’t explicitly know how y is determined by x, when calculating the derivative of y, we use the chain rule and write dy/dx as the derivative of y. • After determining term-by-term derivatives, carry out all necessary algebra steps to isolatedy/dx. That’s our goal! MAT 145
Derivatives of Implicitly Defined Functions (3.5) Try These: MAT 145
Derivatives of Logarithmic Functions (3.6) What is the derivative of the natural log function y = ln(x)? MAT 145
Derivatives of Logarithmic Functions (3.6) Now apply this to other log functions: MAT 145
Derivatives of Logarithmic Functions (3.6) And extend this to other functions: MAT 145
Assignments WebAssign • 3.4 (Part 2), 3.5, 3.6 (two parts) assignments up for completion. • Gateway Derivatives Quiz #2 returned today. GDQ #3 next week! • Test #3: Friday, March 8. MAT 145